1. Field of the Invention
The present invention generally relates to a display device. Particularly, the present invention relates to a display device that can simultaneously display images as well transparently view the background and an image display method thereof.
2. Description of the Related Art
In recent years, flat panel display devices have been widely used in various fields as simply display devices or may also be implemented into electronic devices to be used as devices for the display of data. There are many types of flat panel display devices, wherein liquid crystal display devices are currently the most commonly seen flat panel displays.
FIG. 1 illustrates a schematic diagram of a conventional liquid crystal display device. As shown in FIG. 1, the conventional liquid crystal display device includes a backlight module 10, a liquid crystal panel 30, and a color filter film 50. The backlight module 10 generates backlight 11 and emits the backlight 11 towards the liquid crystal panel 30. An upper polarizer film 31 and a lower polarizer film 33 are separately disposed on two sides of the liquid crystal panel 30. When the backlight 11 passes through the lower polarizer film 33, the lower polarizer film 33 polarizes the backlight 11 such that the backlight 11 has the same polarization direction as the lower polarizer film 33. The backlight 11 then enters the liquid crystal panel 30 and undergoes polarization modulation by the arrangement of liquid crystal molecules of each pixel within the liquid crystal panel 30. The backlight 11 then passes through the color filter film 50 to be filtered of unwanted color spectrums. When the backlight 11 exits the liquid crystal panel 30 and arrives at the upper polarizer film 31, the upper polarizer film 31 controls amount of light of each pixel by only allowing the part of the backlight 11 that has the same polarization direction as the upper polarizer film 31 to pass through while blocking the part of the backlight 11 that has a polarization direction perpendicular to the polarization direction of the upper polarizer film 31.
In terms of these types of conventional liquid crystal display devices, the conventional liquid crystal display device may only display images. They are themselves not transparent to allow the background behind the device to be seen through the device from the front. However, in certain situations, such as the heads-up display (HUD) on the windshield of automobiles or information displays on display cabinets, there may be a need for displaying images while also simultaneously allowing background objects to be viewed through the display device. Therefore, the conventional liquid crystal display device is unable to satisfy these types of requirements.